Means for vacuum sealing packages



March 1s, 1941. s H BERCH 2235394' MEANS FOR VACUUM SEALING PACKAGESFiigd July 11, 1939 Eigf 25 .a2 3/ ZF Patented Marr-18, .1941

l*UNITED STATES PATENT OFFICE vSamuel H. Bei-ch, Beverly Hills, Calif.Application July 11, 1939, Serial No. 283,794

6 Claims.

This invention relates to packaging machinery and particularly pertainsto means for vacuum sealing packages and isa continuation in part of myapplication entitled Method and means of packaging and vacuum sealingproducts," filed June 13, 1939, Serial No. 279,150.

In the packaging of various products within a bag-like container capableof maintaining a vacuum seal, as shown in my application of which thisis a continuation in part, it is necessary to flll the container andthereafter exert suction action upon the container and its contentsprior to forming a tight and permanent seal across the mouth of the lledcontainer. When the product to be sealed within the container is finelydivided material, such for example as ground coiee, considerablediillculty has been experienced in forming a tight seal and seam acrossthe mouth of the bag since there is a tendency for the finely dividedmaterial to be drawn upwardly into the mouth of the bag by suction. Anundesirable amount of this material may be trapped in the seam which-isbeing formed. This causes an imperfect scam to be made and will preventthe package from being permanently vacuum sealed. It is the principalobject of the present invention, therefore, to provide means whereby aflexible container may be filled with a finely divided product,thereafter subjected to vacuum action and then sealing the mouth of thecontainer while holding the same in a manner to prevent the seepage ofthe granular product into the seam as it is being formed and sealed,whereby the package will be permanently vacuum sealed in an automaticmechanical operation.

The present invention contemplates the provision of a mold designed toreceive a package to be vacuum sealed and over which mold a vac- 0 uumhead is applied to exert a suitable suction action on the package andits contents, the structure including means for folding the mouth of thecontainer and holding the mouth snfilciently tight to prevent nelydivided material from being drawn between the abutting faces of the heldportion while sealingthe same.

The invention is illustratedby way of example in the laccompanyingdrawing, in which:

Figure 1 is a view in vertical lsection and elevation showing :a packagemold, the vacuum the present invention Ais particularly concerned.

Fi'g.2 is an enlarged vfragmentary view showing the details ofconstruction of `,the seaxning means. f

I of non-stretching material I4 and an inner sheet head therefor and theseaming means of 'which Fig. 3 is a view drawn on a reduced scale andindicating the manner in which the folding and seaming means isoperated.

`Fig. 4 is a fragmentary view indicating lfolding iingers adapted toform conugations in the seam. 5'

Referring more particularly to the drawing, I0 indicates a mold withinwhich a package II is placed. The package Il is formed with side wallsI2 land I3 which may comprise an outer sheet l0 of stretching material I5. Such a structure is shown in my issued PatentNo. 2,102,716. The innersheet of stretchable material is preferably a rubber compound, such forexample as Pliofilm. 'This material has the characteristic of beingcapable of heat sealing. The horizontal section of the mold` I0 issubstantially rectangular and the depth of the mold is such as toprovide an upper length of the side walls I2 and I3 which extends abovethe level to which the package i`s lled. I'his mouth portion isindicated at I6 in the drawing. Mounted around the mouth of the mold I0is a pan I'I which has a horizontal wall' portion and a marginal flangewhich extends upwardly and is fitted with a lip I8 at its upper edge. Amovable vacuum head I9 is provided to be positioned over the `mouth ofthe pan I1 and to form a hermetical seal 'therewith. A suitable gasketI9' rests upon the lip I8 to provide this seal. A suction pipe 20 is-30carried by the' head and communicates with the space in the mold throughsuction ducts .2L Mounted within the pan Il and above the mold I0 arefolding fingers 22 and 23. These ngers swing vertically and' are carriedupon pivot pins .2l and 25. Normally the folding ngers 22 and 23vstandvertically, -as indicated in Fig. 3 of the drawing, and swing downwardly`to their 'horizontally aligned .position as shown `in Figs. 1 and `2.The pins '24 and 25 of the ngers carry gear :segments 2S and 21 whichare in mesh with each other Aand insure 'that the folding .lingers 'willmove in imlson Vin .their operation. Une -of the Apins :is fitted withtrip fingers i128 :and 29 which may yengage operating structures not:shown in the drawing but by which the :gear segments '26 :and 521 .maybe rotated in `alternate i directions.

In `my previously :filed =application the folding ngers 122 and '.23were .indicated as -being of ,50 metal. 'It was .found :in 'operationthat when Vso constructed -the .faces vof 'the Aportion 'I6 of theypackage could vnot be held in sumciently close commet fto A.prevent thelmaterial vwithin the Apackage from being upwardly into the 55 seam whensubjected to suction action. In the present instance the fingers havebeen constructed in a manner to insure that the meeting edges of thepackage will not tend to slip and loosen when subjected to suctionaction, and

that furthermore these edges will be held with sumcient force to preventgranular material from seeping into the seam to be formed while allowingthe suction action to evacuate the container and permit it to then besealed.

'I'he construction of the folding fingers is particularly shown in Fig.2 of the drawing. Here it will be seen that the finger 23 has a flatbottom face 33 which folds down upon the wall section I3 for a distancesubstantially one-half Aof the width of the package. The free end of thefinger 23 is substantially square, as indicated at 3|, and when in itsfolding position stands vertically. A relatively thin tongue or blade 32is formed as a part of the finger adjacent the free end. This tongue hasan upper face 33 substantially parallel to the lower face 3|I.'4 Anlobliquely disposed sealing face 34 is formed on the back of the finger23. 'I'he folding finger 22 has a face 35 which extends fora distancesubstantially halfway the width of the package II, and when the ngers 22and 23 are in their folding positions the faces 35 and 33, respectively,of these fingers will lie in a common horizontal plane. At the free endof the folding finger 23 there is a blade 36 which overhangs the bladeportion 32 of the nger23. A shoulder 31 is formed on the folding finger22 beneath the blade and in the folded positions of the fingers standsparallel to the end face 3| of the finger 23. `At this particular timethese faces are spaced apart substantially the distance represented bythe thickness of the Wall sections I2 and I3 which are, collapsedagainst each other to form the mouth portion I6. The blade portion 36has a face 33 which is parallel to the face 35 and overhangs the blade32. 'I'he spacing between the contiguous faces of the blades 32 and 36is such as to insure that the mouth of the container will be fully.collapsed and held in this position sufliciently tight to prevent largegrains of nely divided material from the package to be drawn up into theseam to be formed at the mouth of the container. Overhanging the bladeportion 36 of the folding finger 22 is a rubber blade 39 which issuitablysecured to the folding finger 22, such as by the screw 40. lThelower face 4I of the rubber blade 39 lies in substantially the sameplane as the face 33 of the blade portion 36. Thus, when the finger 22is down in its folded position it will compress the mouth portion of thepackage against the blade 32 of the folding finger 23. The rubber blade39 will act to hold the abutting faces of the mouth portion I6 ofthepackage rmlyso that small particles of powder flneness will not be drawninto the seam, while permitting suction action to take place through theseam. It is also to be pointed out that vthe rubber blade 39 willyieldably press against the walls forming the mouth portion I6 of thepackage so that a uniform pressure will be exerted against these wallsirrespective of minute irregularities which may occur in the thicknessof the sheets of material.

It is also to be pointed out that in view of the 'fact that the rubberblade 39 will frictionally engage the walls of the mouth of the packagethere will not be an opportunity for the wall portions to slip withrelation to Aeach other. If the wall portions do tend to slip while theseam is being formed the seam will pucker and a vacuum-tight seal willnot be provided. The use ment 43 is incorporated within the heat sealingmember 4| As shown in Fig. 1, the heat sealing element is mounted on'astud 44 carried in a boss 45 of a supporting lever 46. This lever inturn is pivotally mounted within a bearing 41 upon a pin 43. The bearing41 is carried as a part of the vacuum head I9. Suitable supporting meansare provided for the free end of the lever 46 and comprises a nger 53mounted upon a rock shaft 5I. This is operated by suitable mechanismwith which the present invention is not concerned.

In operation of the present invention the package I| is placedwithin themold I with the portion I6 extending upwardly above the top of the moldand within the pan I1. The folding fingers 22 and 23 are properlyadjusted upon the pins 24 and 23 so that as' the gears 26 and 21 -rotatein unison the finger 23 will fold down first with the finger 22 inoverlapping relation thereto. As these fingers fold downwardly to theposition shown in Fig. 2 of the drawing the side walls I2 and I3 of thepackage will be folded toward each other at the upper end of the`package and the mouth portions I6 will be closed.

As the finger 22 folds over the finger23 the mouth portion I6 will befolded down upon the face 33 of the blade portion 32 of the foldingfinger 23 and then at an inclination. along the face 34. Ihis mouthportion will be held down by the overlapping folding nger 22 since itsmetal face 33 will fold down over the material and exert pressureagainst the seam portion I3 to exclude granularmaterial from the seam.At

the same time the rubber b1ade39 will fold downagainst the portion I6 ofthe package and will yieldably hold that portion against the face 33 ofthe folding finger 23. When suction action Iis then exerted upon thepackage through the pipe 2li and the ducts 2| the 4air will be exhaustedfrom the package but the material therein will be entrapped. It is to beunderstood that the face of 'the rubber blade 39 may be of any desiredtexture. That is to say, it may be' smooth, corrugated, or otherwiseroughened without departing from the spirit of the invention.

After the package has been acted upon by the two folding fingers 22 and23 to hold the mouth I6 of the package in a clamped position the heatingelement 4I is lowered against the outer length of the portion I6 of thepackage. Heat and pressure will thus be supplied in a suflicient degreeto cause the Pliolm forming the inner liner I to be heat-sealed alongits abutting faces. Thus, the contents of the package will be subjectedto a vacuum action, after which the mouth portion of the package will bethoroughly heatsealed without any possibility for extraneous matter fromthe package to be drawn into theseal and to make an imperfect seam.

It will thus be seen that the structure here disclosed provides simpleand effective means whereby a flexible container may be vacuum sealedand extraneous matter will be excluded from the seam, therebyinsuringthat a tight seam and a permanent seal are readily effected.

While I have shown the preferred form of my invention as now known tome, it will be understood that various changes may be madeincombination, construction, and arrangement of parts by those skilled inthe art, without departing from the spirit of my invention as claimed.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In a package sealing machine, a mold into which a flexible filledpackage is placed, the mouth of the package being sealed by formingastraight seam entirely across the top of the package with the innerabutting faces sealed together,

a pair of folding fingers carried by the mold at opposite sides of thepackage, means for folding said fingers down against the side walls ofthe package whereby the side walls of the package will be foldedtogether along substantially the median line of the package and wherebythe side walls will be held in their folded position, and sealing meansacting along said abutting seam to cause the abutting faces to cohere.

2. Same as 1, adding the following: said folding fingers operating insequence whereby their free ends will overlap in holding the Walls ofthe mouth of the package together.

3.' In a package sealing machine, a mold into which a flexible filledpackage is placed, the mouth of the 'package being sealed by forming astraight seam entirely across the top of the package with the innerabutting faces sealed together, a pair of folding fingers carried by themold at opposite sides of the package, means for folding said fingersdown against the side walls of the package whereby the side walls of thepackage will be folded together along substantially the means actingalong said abutting seam to causev the abutting faces to cohere, saidfolding fingers operating in sequence whereby their free ends willoverlap in holding the walls of the mouth of the package together, andyieldable means on the free ends of the said fingers for exerting ayieldable pressure against the folded Walls of the package. l

4. Same as 3, adding the following: said yieldable means being in theform of a rubber pressure member.

5. In a package sealing machine, a mold structure within which a packagemay be sealed under vacuum, a pair of folding fingers mounted uponopposite sides of the mouth of the package by which the opposite sideWalls of the package may be folded in against each other along themedian line of the package and throughout the length of the mouth of thepackage, rubber elements carried on the free ends of said ngers to exerta yielding force against the opposite sides of the folded mouth ofthepackage, and sealing means acting against the folded mouth of thepackage when thus held to seal the same under vacuum.

6. Same as 5, adding the following: said mold being provided with aconduit to communicate with suction exerting means acting to subject thepackage and its contents to suction while the mouth of the package isheld closed and prior to the action of the sealing means.

SAMUEL H. BERCH.

